Opencv python HoughLinesP strange results

Question

I\'m trying to get the same result they got in this tutorial for HoughLinesP filter. I took same images and same threshold values like this :

import cv2
fro         


        

Answer 1

The problem in your code was how the returned lines are arranged. This piece of code works for me:

import cv2
import numpy as np

img = cv2.imread('building.jpg',1)
cannied = cv2.Canny(img, 50, 200, 3)
lines = cv2.HoughLinesP(cannied, 1, np.pi / 180, 80, 30, 10)

for line in lines:
    leftx, boty, rightx, topy = line[0]
    cv2.line(img, (leftx, boty), (rightx,topy), (255, 255, 0), 2)

cv2.imwrite('lines.png',img)
cv2.imwrite('canniedHouse.png',cannied)
cv2.imshow('', img)
cv2.waitKey(0)
cv2.destroyAllWindows()

I also did some other small changes in order to get the code running on my machine.

I think you need to change some parameters in order to get exactly same results as in the documentation.